The use of CAWI (Computer-Assisted Web Interviews) has increased greatly over the last decade, partly driven by technological development and increased Internet penetration, and partly by falling response rates in the traditional modes of polling (Baker et al., 2010; Curtin, Presser, & Singer, 2005; Couper 2000; Hansen, 2007).
While some studies have found potential disadvantages to CAWI, e.g., higher levels of “don’t know” answers and high levels of break off (Heerwegh & Loosveldt, 2008; Peytchev, 2009), research also shows many advantages of CAWI compared to traditional modes: They are cost-efficient, allow automatic correction of errors and omissions during the interviews (Alvarez & Beselaere, 2005), and they lessen problems with social desirability bias towards interviewers (Baker et al., 2010; Kreuter, Presser, & Tourangeau, 2008). Furthermore, using web panels to conduct recurring CAWI with the same group of respondents let us build true time-series data which mitigates the problem of endogeneity inherent in so many public opinion studies. Additionally, modest differences are found when comparing results from web panels with traditional modes of surveys (Sanders, Clark, Stewart, & Whiteley, 2007), and web panels even display higher levels of data reliability than telephone surveys in some studies (Braunsberger, Wybenga, & Gates, 2007). One of the key challenges for web panels is recruitment of members. While numerous studies have investigated strategies to increase response rates …